Add firstVertex to QGeometryRenderer API

To support glDrawArraysInstancedBaseInstance

Task-number: QTBUG-51515
Change-Id: I0c95b351ff7a3668f17256d0d875c3c36537fd01
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

5 files changed, 43 insertions, 0 deletions

diff --git a/src/render/geometry/geometryrenderer.cpp b/src/render/geometry/geometryrenderer.cpp
index bc89a968c..da8b1aca0 100644
--- a/src/render/geometry/geometryrenderer.cpp
+++ b/src/render/geometry/geometryrenderer.cpp
@@ -63,6 +63,7 @@ GeometryRenderer::GeometryRenderer()
     , m_vertexCount(0)
     , m_indexOffset(0)
     , m_firstInstance(0)
+    , m_firstVertex(0)
     , m_restartIndexValue(-1)
     , m_verticesPerPatch(0)
     , m_primitiveRestartEnabled(false)
@@ -83,6 +84,7 @@ void GeometryRenderer::cleanup()
     m_vertexCount = 0;
     m_indexOffset = 0;
     m_firstInstance = 0;
+    m_firstVertex = 0;
     m_restartIndexValue = -1;
     m_verticesPerPatch = 0;
     m_primitiveRestartEnabled = false;
@@ -108,6 +110,7 @@ void GeometryRenderer::initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBase
     m_vertexCount = data.vertexCount;
     m_indexOffset = data.indexOffset;
     m_firstInstance = data.firstInstance;
+    m_firstVertex = data.firstVertex;
     m_restartIndexValue = data.restartIndexValue;
     m_verticesPerPatch = data.verticesPerPatch;
     m_primitiveRestartEnabled = data.primitiveRestart;
@@ -140,6 +143,9 @@ void GeometryRenderer::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e)
         } else if (propertyName == QByteArrayLiteral("firstInstance")) {
             m_firstInstance = propertyChange->value().value<int>();
             m_dirty = true;
+        } else if (propertyName == QByteArrayLiteral("firstVertex")) {
+            m_firstVertex = propertyChange->value().value<int>();
+            m_dirty = true;
         } else if (propertyName == QByteArrayLiteral("restartIndexValue")) {
             m_restartIndexValue = propertyChange->value().value<int>();
             m_dirty = true;
diff --git a/src/render/geometry/geometryrenderer_p.h b/src/render/geometry/geometryrenderer_p.h
index 640840962..3399e6f70 100644
--- a/src/render/geometry/geometryrenderer_p.h
+++ b/src/render/geometry/geometryrenderer_p.h
@@ -81,6 +81,7 @@ public:
     inline int vertexCount() const { return m_vertexCount; }
     inline int indexOffset() const { return m_indexOffset; }
     inline int firstInstance() const { return m_firstInstance; }
+    inline int firstVertex() const { return m_firstVertex; }
     inline int restartIndexValue() const { return m_restartIndexValue; }
     inline int verticesPerPatch() const { return m_verticesPerPatch; }
     inline bool primitiveRestartEnabled() const { return m_primitiveRestartEnabled; }
@@ -102,6 +103,7 @@ private:
     int m_vertexCount;
     int m_indexOffset;
     int m_firstInstance;
+    int m_firstVertex;
     int m_restartIndexValue;
     int m_verticesPerPatch;
     bool m_primitiveRestartEnabled;
diff --git a/src/render/geometry/qgeometryrenderer.cpp b/src/render/geometry/qgeometryrenderer.cpp
index 716417bc5..87ca16f11 100644
--- a/src/render/geometry/qgeometryrenderer.cpp
+++ b/src/render/geometry/qgeometryrenderer.cpp
@@ -57,6 +57,7 @@ QGeometryRendererPrivate::QGeometryRendererPrivate()
     , m_vertexCount(0)
     , m_indexOffset(0)
     , m_firstInstance(0)
+    , m_firstVertex(0)
     , m_restartIndexValue(-1)
     , m_verticesPerPatch(0)
     , m_primitiveRestart(false)
@@ -92,6 +93,12 @@ QGeometryRendererPrivate::QGeometryRendererPrivate()
 /*!
  * \qmlproperty int GeometryRenderer::firstInstance
  *
+ * Holds the first vertex.
+ */
+
+/*!
+ * \qmlproperty int GeometryRenderer::firstVertex
+ *
  * Holds the base instance.
  */
 
@@ -213,6 +220,17 @@ int QGeometryRenderer::firstInstance() const
 }
 
 /*!
+ * \property QGeometryRenderer::firstVertex
+ *
+ * Holds the base vertex.
+ */
+int QGeometryRenderer::firstVertex() const
+{
+    Q_D(const QGeometryRenderer);
+    return d->m_firstVertex;
+}
+
+/*!
  * \property QGeometryRenderer::restartIndex
  *
  * Holds the restart index.
@@ -316,6 +334,16 @@ void QGeometryRenderer::setFirstInstance(int firstInstance)
     emit firstInstanceChanged(firstInstance);
 }
 
+void QGeometryRenderer::setFirstVertex(int firstVertex)
+{
+    Q_D(QGeometryRenderer);
+    if (d->m_firstVertex == firstVertex)
+        return;
+
+    d->m_firstVertex = firstVertex;
+    emit firstVertexChanged(firstVertex);
+}
+
 void QGeometryRenderer::setRestartIndexValue(int index)
 {
     Q_D(QGeometryRenderer);
@@ -423,6 +451,7 @@ Qt3DCore::QNodeCreatedChangeBasePtr QGeometryRenderer::createNodeCreationChange(
     data.vertexCount = d->m_vertexCount;
     data.indexOffset = d->m_indexOffset;
     data.firstInstance = d->m_firstInstance;
+    data.firstVertex = d->m_firstVertex;
     data.restartIndexValue = d->m_restartIndexValue;
     data.verticesPerPatch = d->m_verticesPerPatch;
     data.primitiveRestart = d->m_primitiveRestart;
diff --git a/src/render/geometry/qgeometryrenderer.h b/src/render/geometry/qgeometryrenderer.h
index a6d211c7a..cc4560921 100644
--- a/src/render/geometry/qgeometryrenderer.h
+++ b/src/render/geometry/qgeometryrenderer.h
@@ -60,6 +60,7 @@ class QT3DRENDERSHARED_EXPORT QGeometryRenderer : public Qt3DCore::QComponent
     Q_PROPERTY(int vertexCount READ vertexCount WRITE setVertexCount NOTIFY vertexCountChanged)
     Q_PROPERTY(int indexOffset READ indexOffset WRITE setIndexOffset NOTIFY indexOffsetChanged)
     Q_PROPERTY(int firstInstance READ firstInstance WRITE setFirstInstance NOTIFY firstInstanceChanged)
+    Q_PROPERTY(int firstVertex READ firstVertex WRITE setFirstVertex NOTIFY firstVertexChanged)
     Q_PROPERTY(int restartIndexValue READ restartIndexValue WRITE setRestartIndexValue NOTIFY restartIndexValueChanged)
     Q_PROPERTY(int verticesPerPatch READ verticesPerPatch WRITE setVerticesPerPatch NOTIFY verticesPerPatchChanged)
     Q_PROPERTY(bool primitiveRestartEnabled READ primitiveRestartEnabled WRITE setPrimitiveRestartEnabled NOTIFY primitiveRestartEnabledChanged)
@@ -92,6 +93,7 @@ public:
     int vertexCount() const;
     int indexOffset() const;
     int firstInstance() const;
+    int firstVertex() const;
     int restartIndexValue() const;
     int verticesPerPatch() const;
     bool primitiveRestartEnabled() const;
@@ -106,6 +108,7 @@ public Q_SLOTS:
     void setVertexCount(int vertexCount);
     void setIndexOffset(int indexOffset);
     void setFirstInstance(int firstInstance);
+    void setFirstVertex(int firstVertex);
     void setRestartIndexValue(int index);
     void setVerticesPerPatch(int verticesPerPatch);
     void setPrimitiveRestartEnabled(bool enabled);
@@ -117,6 +120,7 @@ Q_SIGNALS:
     void vertexCountChanged(int vertexCount);
     void indexOffsetChanged(int indexOffset);
     void firstInstanceChanged(int firstInstance);
+    void firstVertexChanged(int firstVertex);
     void restartIndexValueChanged(int restartIndexValue);
     void verticesPerPatchChanged(int verticesPerPatch);
     void primitiveRestartEnabledChanged(bool primitiveRestartEnabled);
diff --git a/src/render/geometry/qgeometryrenderer_p.h b/src/render/geometry/qgeometryrenderer_p.h
index 3341a7758..465c7fdca 100644
--- a/src/render/geometry/qgeometryrenderer_p.h
+++ b/src/render/geometry/qgeometryrenderer_p.h
@@ -71,6 +71,7 @@ public:
     int m_vertexCount;
     int m_indexOffset;
     int m_firstInstance;
+    int m_firstVertex;
     int m_restartIndexValue;
     int m_verticesPerPatch;
     bool m_primitiveRestart;
@@ -85,6 +86,7 @@ struct QGeometryRendererData
     int vertexCount;
     int indexOffset;
     int firstInstance;
+    int firstVertex;
     int restartIndexValue;
     int verticesPerPatch;
     bool primitiveRestart;